ks, but this usage has now entirely disappeared.

157. _Sonata-form_ (sometimes called _sonata-allegro_) is a plan for the
construction of instrumental music (sonatas, quartets, symphonies,
etc.), in which three rather definite divisions always occur, the third
division being a more or less literal repetition of the first.

These _three parts of sonata-form_ with their usual
subdivisions are:

I. EXPOSITION

(1) Principal theme (or first subject).

(2) Link-episode (or modulation group).

(3) Secondary theme (or song group), always in a nearly
related key.

(4) Closing group.

(5) Coda.

II. DEVELOPMENT SECTION

Treating the themes introduced in the exposition in an almost
infinite variety of fashions, according to the principles of
thematic development. (See Sec. 148).

III. RECAPITULATION (OR REPRISE)

Consisting essentially of the same subdivisions found in the
_exposition_, but differing from this first section in one
essential point, viz., that instead of stating the secondary
theme in a _related_ key, the entire recapitulation is in the
_principal_ key. This third section is always followed by a
coda (which may either be very short or quite extended),
bringing the whole movement to a more definite close.

The second part of _sonata-form_ (the development section) is
sometimes the longest and most intricate of the three
divisions, and it is at this point that the composer has an
opportunity of displaying to the full his originality and
inventive skill. It is principally because of this development
section that the sonata is so far superior as a _form_ to its
predecessors. For an analyzed example of _sonata-form_, see
Appendix E. The student is advised to take other sonatas and
go through the first movements with a view to finding at least
the three main divisions mentioned above. In some cases the
form will of course be so irregular that all the parts
indicated cannot be discovered, but the general outlines of
the scheme will always be present.

158. A _sonatina_, as its name implies, is a little sonata. It differs
from the sonata proper principally in having little or no development,
the second section being of slight importance as compared with the
corresponding section of a sonata.

A _grand sonata_ is